Labeled drill pipe

ABSTRACT

A drill pipe including a tube having opposite ends. An internally threaded connector is provided at one of the opposite ends of the tube. An externally threaded connector is provided at the other one of the opposite ends of the tube. The externally threaded connector is adapted to mate with the internally threaded connector on a second drill pipe. A bar code is etched into either the tube, the internally threaded connector, or the externally threaded connector.

FIELD OF THE INVENTION

The present invention relates generally to card, picture, and signexhibiting and, more particularly, to checks, labels and tags carried oncylindrical objects.

BACKGROUND OF THE INVENTION

Rotary drilling is the act of making a hole in the earth through whichhydrocarbons can be produced if encountered in commercial quantities.During rotary drilling, a weighted bit is fastened to, and rotated by, adrill string, comprising drill pipe and drill collars, with new sectionsor joints being added as drilling progresses. The cuttings are liftedfrom the hole by a drilling fluid which is pumped down the inside of thedrill string, through nozzles in the bit, and upward through the annularspace between the drill string and the wall of the hole. At the surface,the returning drilling fluid is passed through a series of tanks or pitswithin which cuttings are separated and fluid treatments areaccomplished. The drilling fluid is drawn from the last of the pits torepeat the cycle.

The drill pipe must be removed from the hole in order to replace the bitor to place the hole in condition to produce hydrocarbons if they arefound. The pipe is pulled in stands of two to four joints each. When thedrilling of a hole is finished, the pipe joints are separated from oneanother and transported to a new drilling location. If drilling is notscheduled to commence at another location, the pipe joints are often setin racks at a storage depot for convenient access when needed.

Oilfield drillers have had great difficulties tracking drill pipe whileit is in transport and storage. Joints of pipe having a given diameterand tool joint type look substantially identical to one another eventhough their histories of manufacture and use are very different. Thus,old, heavily used, and failure-prone drill pipe can be confused withnewer, trouble-free drill pipe. Mix-ups can be catastrophic, potentiallyresulting in a loss of: human life, drilling equipment, and productiveoil and gas wells.

Efforts have been made to mark drill pipe so that it can be more easilytracked. Perhaps the earliest technique tried involved stamping drillpipe with unique numbers and other indicia. Stamping is simply andeasily accomplished by driving a die against a drill pipe with a greatforce such as that resulting from the blow of a hammer. Unfortunately,such blows create small, local fractures in the drill pipe. Thesefractures define weak spots in the drill pipe that can cause it toeventually fail.

Others tried marking drill pipe with radio frequency identification(RFID) tags. The RFID tags were small; flat; resistant to shocks,moisture and dirt; and were adhesively attached to the drill pipe. Thesetags possessed a read only memory for data storage and an antenna forbroadcasting stored data. The tags were powered and read by inductivecoupling. Inductive coupling utilizes a coil element that is energizedby a coded RF signal from a tag reader to provide power to the tagcircuitry. The tag coil modulates and reflects the incident RF carriersignal back to the tag reader to transfer stored data from the tag tothe tag reader, which receives and decodes the data. Read ranges weregenerally on the order of several inches.

In use, the RFID tags communicated with a tag-reading device to conveyan identification number to a computer that used the identificationnumber to access specified files in its digital memory. Once accessed,the files could be manipulated and displayed to provide the history ofthe drill pipe. Additionally, the files could be updated withadditional, historical data about the drill pipe. While the marking ofdrill pipe with RFID tags avoided the cracking problem caused bystamping, the tags tended to fall off and become lost during rotarydrilling operations. Thus, RFID-tagged drill pipe was not widelyaccepted by oilfield drillers.

SUMMARY OF THE INVENTION

In light of the problems associated with placing identifiers on drillpipe in the past, it is a principal object of the invention to provide adrill pipe with at least one, engraved, bar code label. The bar codelabel would typically display an alphanumeric code that would allow theassociated drill pipe to be tracked for purposes of theft prevention andinventory control. Additional information associated with the:manufacture, maintenance, storage, and use of the labeled drill pipe canbe stored in the computer databases and retrieved with the alphanumericcode. The databases associated with a particular alphanumeric code canalso be updated when desired.

It is a further object of the invention to provide a drill pipe with alabel that is likely to last for the life of the drill pipe. The labelcannot fall off of the drill pipe and is positioned in such a way as tominimize wear and degradation thereof. The label can comprise: atrademark, a logo, a serial number, an alphanumeric code, and any othersort of indicia identifying the source of the drill pipe or quality ofthe drill pipe.

It is another object of the invention to provide a labeled drill pipe ofthe type described that is undamaged by the labeling process thusretaining its inherent corrosion-resistance, strength and durability.Thus, the labeled drill pipe is expected to have a lengthy service life.

It is an object of the invention to provide improved features andarrangements thereof in a labeled drill pipe for the purposes describedthat is robust in construction, reasonably inexpensive to manufacture,and fully dependable in use.

Briefly, my drill pipe achieves the intended objects by featuring a tubehaving opposite ends. An internally threaded connector is provided atone of the opposite ends of the tube. An externally threaded connectoris provided at the other one of the opposite ends of the tube. Theexternally threaded connector is adapted to mate with the internallythreaded connector on a second drill pipe. A bar code is etched intoeither the tube, the internally threaded connector, or the externallythreaded connector.

The foregoing and other objects, features, and advantages of my labeleddrill pipe will become readily apparent upon further review of thefollowing detailed description of the embodiment illustrated in theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

My labeled drill pipe can be more readily understood with reference tothe accompanying drawings, in which:

FIG. 1 is a side elevational view of a preferred embodiment of mylabeled drill pipe with portions broken away to reveal details thereof.

FIG. 2 is an enlarged view of the encircled area, designated “2”, inFIG. 1.

FIG. 3 is an enlarged, vertical, cross-sectional view of the male tooljoint of the labeled drill pipe of FIG. 1.

FIG. 4 is a perspective view of the male tool joint and tube of analternative embodiment of my labeled drill pipe.

Similar reference characters denote corresponding features consistentlythroughout the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the FIGS., a drill pipe constructed in accordance withmy invention is shown at 10. The drill pipe 10 is a hollow, cylindrical,seamless tube 12 having a pair of connectors or tool joints 14 and 16affixed to its opposite ends. The drill pipe 10 is labeled with a barcode 18 applied to the tool joint 16. The bar code 18 is unique to thedrill pipe 10 and is used to identify the drill pipe 10 throughout itslife.

The tube 12, and hence the drill pipe 10, is specified by its outsidediameter, weight per foot, steel grade, and length. These parameters area matter of design choice (and can vary widely), but are usuallyselected for an optimum combination of strength, hardness, and fatigueresistance. The American Petroleum Institute (API) has adopted standardsmeant to reinforce safe drilling practices by setting these parameterswithin fixed ranges. The tube 12 would normally be configured to meetAPI standards.

In selecting a tube 12 of appropriate size and weight for a particulardrilling operation, the diameter and depth of the hole to be drilled aregiven first consideration. Small diameter holes require the use ofsmaller tubes 12. Conversely, large diameter holes necessitate the useof larger tubes 12. In all cases, the tube 12 must be sufficiently largeand heavy to afford adequate strength to the drill string so that itwill not break during use.

The tube 12 must provide adequate room for the flow of drilling fluidand suspended cuttings. In this regard, the user must seek a compromisebetween flow resistance inside and outside of the drill string. Theinside diameter of tube 12 must be as large as possible to keep pressurelosses therein low. Additionally, the outside diameter the tube 12 mustbe as small as possible to minimize pressure losses as drilling fluidmoves past the walls of the drilled hole.

Tool joints 14 and 16 are threaded fasteners designed to facilitatecoupling and uncoupling of multiple tubes 12 forming a drill string. Thetool joints 14 and 16 are configured to avoid stripping under severestrains. Additionally, the tool joints 14 and 16 are internally flush sothat the openings through the tool joints 14 and 16 are equal in size tothat through the tube 12 itself to minimize pressure losses. The API haslisted specifications for some tool joints, but many variations havebeen developed.

Each of the tool joints 14 and 16 provides a threaded connection to itsopposite counterpart on another tube 12. The tool joint 14 has helicalthreads 20 machined on the inside and provides the drill pipe 10 with afemale end commonly referred to as a “box.” The tool joint 16, however,has helical threads 22 machined on the outside that are adapted to matewith the threads 20 of a second drill pipe 10. The threads 22 andprovide the drill pipe 10 with a male end commonly called a “pin.” Whentwo drill pipes 10 are joined together, the pin of one drill pipe 10 isstabbed into the box of another drill pipe 10 and the connection istightened by screwing the two drill pipes 10 together.

Tool joints 14 and 16 are made of steel, selected and heat-treated foran optimum combination of strength, hardness, and fatigue resistance. Toreduce scouring, and turbulence, and pressure loss in ascending drillingfluids, the exterior surfaces of the tool joints 14 and 16 arestreamlined. That is, the bottom surface 24 of the tool joint 20 and thetop surface 26 of the tool joint 22 are tapered. Additionally, theexternal diameters of the outer walls, respectively 28 and 30, of tooljoints 14 and 16 are maintained as small as is consistent with strengthand tolerance for abrasive wear. Portions likely to be scoured bytransported cuttings, particularly the surfaces 24 and 26, can beprotected with coatings of hard-faced fusion metals.

Tool joint threads 20 and 22 are customarily V-shaped and inclined at60° and may have rounded crests and troughs. The form and dimensions ofthreads 20 and 22 are specified by API standards. Nonetheless, somemanufacturers employ threads 20 and 22 of special form, designed tofacilitate rapid coupling and uncoupling, or to increase the security ofa tool joint. For example, square threads and modified square threadsare sometimes used.

API standards prescribe tool joints that can be attached to tubes 12 bymeans of threaded connections, other means are often employed. Tooljoint 14 thus has internal, helical threads 32 provided in its bottomend for this purpose. Similarly, tool joint 16 is provided at its topend with internal, helical threads 34 for threaded attachment to tube12. The connection between the tool joints 14 and 16 and the tube 12 canalso be made by welding. Furthermore, the tool joints 14 and 16 can alsobe integrally formed with tube 12 so that they comprise a unitarystructure with the tube 12, perhaps resulting in a more secureconnection. However, tool joints 14 and 16 are subjected to considerablewear, and repair and replacement become more difficult when the tooljoints 14 and 16 are integrally formed with the tube 12.

A bar code 18 is provided to the beveled, top surface 26 of the tooljoint 16 with the top surface 26 being minimally susceptible to damageor wear during drilling. The bar code 18 includes a plurality ofelevated modules 36 of square outline and a plurality of incised modules38 of square outline fitted within an area measuring about 9/32 inchesby 9/32 inches (7 mm×7 mm). The exterior surfaces of the modules 36 areflush with the top surface 26 and the exterior surfaces of the modules38 are set about 1/32 inches (0.8 mm) into the top surface 26. Themodules 38 can be incised more deeply, say to a depth of about 0.25inches (6.4 mm), but they are more time-consuming and costly to produce.Since a large portion of the bar code 18 can be worn away yet still bemachine readable, making modules 38 with great depth is not particularlyimportant.

The bar code 18 employs the well-known DataMatrix symbology set out insquare or rectangular patterns. DataMatrix is a 2-D bar code thatrepresents text or other information in a pattern of black and whitesquares. (The rough, incised surfaces of modules 38 reflect less lightthan the elevated surfaces of the modules 36 and, thus, appear as blacksquares to a DataMatrix scanner. The more reflective surfaces of themodules 36 appear white to the scanner.) The bar code 18 can carry froma few bytes up to 2 kB of data, depending upon the number of modules 36and 38 contained therein. By adding special data correction data to thebar code 18, it can be read even if it is partially damaged. The errorcorrection level is not adjustable by the user, but it is usuallypossible to restore about 25% of unreadable code.

DataMatrix was developed by RVSI Acuity CiMatrix. After development,this company was acquired by Siemens Energy and Automation, Inc. Thenominative standards for the DataMatrix bar code symbology are called:ISO/IEC 16022:2000 and ISO/IEC 24720:2006 (ISO International Standard).

Since its introduction in the marketplace, DataMatrix has gained aworldwide following. The aerospace, electronics, and automotiveindustries use the DataMatrix symbology for marking parts with lasers.Also, other industries have found that DataMatrix is useful for trackingmail and managing the flow of documents.

The bar code 18 is produced by laser engraving, a very clean and precisetechnique. A computer directing the movements of the laser and nocutting tools come in direct contact with the tool joint 16. Thus, nodulled tools need be replaced as engraving progresses.

A laser engraving machine has two principal components: a laser and acomputer. The laser emits an electromagnetic beam onto the top surface26 of the tool joint 16. The computer controls the direction, intensity,speed of movement, and spread of the laser beam aimed at the top surface26.

There are three main types of laser engraving machines. The most commontype involves the workpiece being held steady as the laser is moved in Xand Y directions. A second type of machine, similar to the first, movesthe laser is fine helixes as the laser is pulsed on and off. In thethird type of machine, both the laser and workpiece are stationary andmirrors move the laser beam over the workpiece surface. It is believedthat any of these types of machines can be adapted to produce a bar code18 on the drill pipe 10.

The point where the laser beam contacts the top surface 26 is usuallythe focal point of the laser's optics. The focal point is typically afraction of a millimeter in size, and only the area within the focalpoint is heated when the laser beam strikes the top surface 26. The heatis so intense that the steel comprising the tool joint 16 maymicroscopically fracture (“glass up”) and flake off the top surface 26thereby incrementally producing the modules 38. An air jet is typicallyemployed to remove the flakes from the top surface 26 as they areformed.

Different patterns of modules 36 and 38 making up bar codes 18representing different code numbers in DataMatrix symbology can beengraved by programming the controlling computer to move the laser beamover different courses. The intensity and speed of movement of the laserbeam is carefully controlled by the computer to achieve remove materialto a consistent depth. Since the position of the laser beam is preciselydetermined by the computer, it is not necessary to mask the top surface26 prior to engraving.

Laboratory test have been performed on the drill pipe 10 labeled withthe bar code 18 to check its integrity. No integrity violations werefound. Localized heating of the tool joint 16 and tube 12 caused by thelaser beam in producing the bar code 18 does not change steelcomposition in a manner that could make it susceptible to hydrogensulfide corrosion or damage by drilling or formation fluids.Furthermore, the laser etching process leaves no fractures in the steelof discernable size. So, the labeled drill pipe 10 is not any morelikely to fail than an unmarked drill pipe.

A bar code reader, having a scanner and a decoder, is used to determinethe code number represented by the bar code 18 on the drill pipe 10. Inuse, light from the scanner is directed onto the bar code 18 with thelight being absorbed by the incised modules 38 and being reflected bythe elevated modules 36. A photocell in the scanner receives thereflected light and converts it into electrical signals. In response,the photocell generates a small electrical signal for the elevatedmodules 36 and a somewhat larger electrical signal for the incisedmodules 38 with the duration of the electrical signals reflecting thepositions of the modules 36 and 38 relative to one another. Thesesignals are “decoded” by the decoder into a number that is, then,delivered to a decoding station in a conventional binary format.

The bar code reader can take a number of different forms. The bar codereader can be: pen-type, laser-type, CCD-type, cell phone-type,camera-based, and omni-directional. Because of their versatility and thelarge size of the drill pipe 10, camera-based bar code readers may bethe optimum sort for use in reading the bar code 18.

A decoding station (not shown) produces useful historical informationabout the drill pipe 10. The decoding station includes a centralprocessing unit (CPU) and a digital memory connected to the CPU. The barcode reader described above is connected to the CPU for gathering a codenumber from the bar code that directs the CPU to data files stored in adigital memory. A keypad is connected to the CPU for inputting data intothe digital memory CPU associated with the drill pipe 10. The keypad isalso used for commanding the CPU to act upon the input data inpreprogrammed ways. The CPU is also connected to an LCD display thatshows the data: accessed from the digital memory, input via the keypad,or developed by the CPU in conjunction with its internal programming.

Much data regarding the drill pipe 10 can be input into the digitalmemory with the keypad. By way of example, the data for a drill pipe 10can include its: code number, manufacturer, location/date ofmanufacture, brand, date of marking, diameter, length, weight,composition, locations/dates of use, numbers of trips into hole,locations/dates of storage, failures, and repairs. The options arelimitless and are dependent on the needs of the user.

The CPU is a conventional microprocessor within which is held a softwareprogram for monitoring the usage of the drill pipe 10. To access theprogram, a code number from the bar code 18 must be provided to the CPUvia the bar code reader or the keypad. The code number directs theprogram to access data files associated with the drill pipe 10 andstored in the digital memory. These files can include data associatedwith the drill pipe's: manufacturer, location/date of manufacture,brand, date of marking, diameter, length, weight, composition,locations/dates of use, numbers of trips into hole, locations/dates ofstorage, failures, and repairs.

The bar code reader can be attached through the keyboard interface tothe CPU so that the decoder can send a code number in key codes exactlyas though the number had been typed into the keypad. (Such a bar codereader is a “wedge reader” since it is connected between a keypad and aCPU and operates as a second keyboard.) The CPU receives the code numberfrom the bar code reader in the same manner in which it would have beenproduced on keypad by a fast typist.

After receiving the code number corresponding with the bar code 18, theCPU can generate a variety of reports for viewing on the LCD display (orfor output to a printer) related to the history of the drill pipe 10. Itis anticipated that with a few keystrokes at the keyboard, the fullhistory of the drill pipe 10 can be retrieved and viewed on the LCDdisplay. This history can include, among other things: manufacturer,location/date of manufacture, brand, date of marking, diameter, length,weight, composition, locations/dates of use, numbers of trips into hole,locations/dates of storage, failures, and repairs of the drill pipe 12.Alternatively, with a few additional keystrokes, the data can bemanipulated to provide selected items of the full history like datarelated to trips or repairs.

The techniques for the manipulation of computer databases, and forretrieving data therefrom, are well known and nothing in thisspecification is meant to limit their use. Thus, the historical dataretrieved from the digital memory associated with the drill pipe 10 andaccessed with the bar code 18 can be of any kind and can be manipulatedin any useful way. In the end, the life of the drill pipe 10 can beeasily tracked from the time of its production until the date of itsdestruction or disposal, something never done before.

While the drill pipe 10 has been described with a high degree ofparticularity, it will be appreciated by those skilled in the field thatmodifications can be made to it. FIG. 4, for example, illustrates adrill pipe 110 that is in all respects the same as that shown in FIGS.1-3 but has a laser-engraved bar code 118 on its tube 112. The bar code118 can be engraved into the tube 12. Similarly, the bar code can beapplied to the bottom surface 24 of the tool joint 14, but the bar codeswould be more somewhat more susceptible to wear or degradation iflocated in these places due to the increased likelihood of contact withthe borehole wall and transported cuttings moving upwardly through theborehole. Furthermore, other labeling indicia can be readily substitutedfor the bar code 18 such as: trademarks, logos, serial numbers, andalphanumeric codes. Therefore, it is to be understood that my inventionis not limited solely to drill pipe 10 described above, but encompassesany and all drill pipes falling within the scope of the followingclaims.

1. A drill pipe, comprising: a hollow tube having opposite ends; afemale tool joint being affixed to one of said opposite ends of saidtube; a male tool joint being affixed to the other one of said oppositeends of said tube, and said male tool joint having a beveled, top wall;and, an incised label being provided on said top wall of said male tooljoint.
 2. The drill pipe according to claim 1 wherein said incised labelis a bar code including a plurality of incised modules and a pluralityof elevated modules positioned side-by-side and arranged in amachine-readable pattern.
 3. A drill pipe, comprising: a hollow,cylindrical, seamless tube having opposite ends; a female tool jointbeing internally threaded and welded to one of said opposite ends ofsaid tube; a male tool joint being externally threaded and welded to theother one of said opposite ends of said tube, and said male tool jointhaving a beveled, top wall; and, a bar code being etched into said topwall of said male tool joint, said bar code including a plurality ofincised modules and a plurality of elevated modules positionedside-by-side and arranged in a machine-readable pattern.
 4. A drillpipe, comprising: a tube having opposite ends; an internally threadedconnector being provided at one of said opposite ends of said tube; anexternally threaded connector being provided at the other one of saidopposite ends of said tube, said externally threaded connector beingadapted to mate with said internally threaded connector on a second saiddrill pipe; and, a bar code being etched into: said tube, saidinternally threaded connector, or said externally threaded connector.